Question & answer
Audience submits and up/down votes each other's responses.
People in the audience submit responses and up/downvote each others responses. The more important issues float to the top allowing the presenter to tackle the most important issues.
More types of activities
Gather individual questions, ideas, and thoughts from the audience.
Ask questions before or after an event that people can answer at their own pace.
True or false
Quickly determine from your audience if a statement is true or false.